1. Technical Field of the Invention
The present invention relates to an internal combustion engine device and is intended to control suction air sucked into an internal combustion engine and also to control a cooling capacity of a radiator of the internal combustion engine.
2. Prior Art
In a common internal combustion engine, there is provided a throttle valve. When the degree of opening of the throttle valve is adjusted, a volume of suction air sucked into the internal combustion engine is controlled so that an output of the engine can be controlled.
In this connection, when the temperature of outside air is low, there is a possibility that the throttle valve, especially the throttle valve for adjusting an idling speed of the engine, the suction air passage of which is small, is frozen so that the throttle valve can not be normally operated.
In order to solve the above problems, Japanese Unexamined Patent Publication No. 3-78537 discloses a technique in which the throttle valve is heated by engine coolant (warm water) so as to prevent the throttle valve from freezing.
In this connection, in the internal combustion engine, a mixture in which air and fuel are mixed with each other is compressed, ignited and burned (exploded) to obtain motive power. Therefore, in the case of cold start, that is, in the case where the engine is started in a cold state, it is easy to evaporate (vaporize) fuel when the temperature of air (suction air) is relatively high. Therefore, the startability of the engine can be enhanced.
On the other hand, in the case where the temperature of suction air is high when the engine temperature has been sufficiently raised after the completion of warming up, the density of suction air (oxygen) is decreased. Accordingly, there is a possibility that the mass of suction air is decreased and the engine output is lowered.
Therefore, the present inventors made investigation into a suction air control system to change over between the case in which air inside the engine compartment (referred to as inside air hereinafter) is supplied to the engine according to a state of operation of the engine and the case in which air outside the engine compartment (referred to as outside air hereinafter) is supplied to the engine. Also, the present inventors made investigations into a radiator control system to control a volume of cooling air flow supplied to the radiator according to a state of operation of the engine.
However, in these investigations, the following problems may be encountered. In the case of supplying outside air to the engine, when the temperature of outside air is low and the throttle valve is heated by warm water to prevent the throttle valve from freezing, the temperature of suction air is raised and the engine output is decreased.
The present invention has been accomplished to solve the above problems. It is an object of the present invention to provide an internal combustion engine device capable of preventing an output of the internal combustion engine from lowering while a suction air volume adjustment means for adjusting a volume of suction air such as a throttle valve is prevented from freezing.
In order to accomplish the above object, the present invention provides an internal combustion engine device comprising: a suction air duct for introducing combustion air into an internal combustion engine; an inside air introducing duct having an inside air suction port for taking in air from an engine compartment into which the internal combustion engine is incorporated, the inside air introducing duct introducing the thus taken inside air into the suction air duct; an outside air introducing duct having an outside air suction port for taking in outside air from the outside of the engine compartment, the outside air introducing duct introducing the thus taken outside air into the suction air duct; an inside and outside air volume adjusting means for adjusting a ratio of a volume of inside air to that of outside air introduced into the suction air duct; a suction air volume adjusting means for adjusting a volume of all air supplied to the suction air duct; a heating means for heating the suction air volume adjusting means, the heating means being capable of variably controlling the heating; and a control means for controlling the suction air volume adjusting means and heating means, wherein when a load of the internal combustion engine is lower than a predetermined value, the inside and outside air volume adjusting means is controlled by the control unit so that the inside air, the volume of which is larger than that of the outside air, can be supplied to the internal combustion engine, and the heating means is controlled so that the suction air volume adjusting means can be heated.
Due to the foregoing, the inside air of relatively high temperature can be sucked into the internal combustion engine, and the air supplied to the internal combustion engine can be heated by the heating means for heating the suction air volume adjusting means. Therefore, the suction air of relatively high temperature can be supplied to the internal combustion engine, and the fuel consumption can be enhanced.
In this connection, in the present invention, the inside and outside air volume adjusting means for adjusting the volumes of the inside and the outside air and the variable throttle means, which is arranged on the downstream side of an air current of the inside and outside air volume adjusting means, for variably controlling the air passage area, compose a suction air volume adjusting means, and the heating means may heat at least the variable throttle means in the suction air volume adjusting means.
When a load of the internal combustion engine is not less than a predetermined value and the outside air temperature detected by the outside air temperature detecting means is lower than a predetermined value, the outside air, the volume of which is larger than that of the inside air, is supplied to the internal combustion engine and the suction air volume adjusting means is heated. Due to the foregoing, according to the operation state (load state) of the internal combustion engine, suction air of an appropriate temperature can be supplied to the internal combustion engine, and further it becomes possible to prevent the suction air volume adjusting means from freezing.
Further, in the present invention, when a load of the internal combustion engine is not less than a predetermined value and the outside air temperature detected by the outside air temperature detecting means is not less than a predetermined value, the outside air, the volume of which is larger than that of the inside air, is supplied to the internal combustion engine and the suction air volume adjusting means is not heated. Then, suction air of relatively low temperature can be supplied to the internal combustion engine when a load given to the internal combustion engine is high. Therefore, the fuel consumption can be more enhanced. In the present invention, the internal combustion engine device further comprises a radiator air flow volume adjusting means for adjusting a volume of an air flow passing through the radiator. Due to the foregoing, the coolant temperature can be adjusted.
In the present invention, the inside and outside air volume adjusting means and radiator air flow volume adjusting means are mechanically linked with each other and operated by one drive means. Due to the foregoing, the number of parts composing the system can be reduced.
In the present invention, the inside and outside air volume adjusting means includes a belt-shaped first opening and closing door for opening and closing an air passage, arranged between the inside air introducing duct and outside air introducing duct, and the radiator air flow volume adjusting means includes a plurality of belt-shaped second opening and closing doors which are arranged in a louver window shape, wherein the first and the second opening and closing door are driven by a link member connected with the drive means.
In the present invention, a support section (25) for pivotally supporting both the opening and closing doors (61, 63) may be arranged on a front end panel arranged in the front end portion of a vehicle extending in the width direction of the vehicle.
In the present invention, the suction air introducing duct (22), inside air introducing duct (23) and outside air introducing duct (24) may be formed on the front end panel.
In the present invention, the front end panel may be formed integrally with a shroud (21) for covering a gap between the radiator (30) and the fan (50), which sends a cooling wind for cooling the radiator (30), so that an air current generated by the fan (50) can not go around the radiator (30).
The present invention will become more apparent from the accompanying drawings and the preferred embodiments of the present invention.